Apparatus and method for sanitizing articles

ABSTRACT

An apparatus is provided for sanitizing an article, the apparatus comprising a housing defining an enclosed internal chamber and having an opening at a door side into the chamber. A door is configured to selectively close the door side of the housing for substantially sealing the chamber. A UV light source is disposed internally of the housing for irradiating the chamber, and an electronic circuit is electrically connected to the UV light source and adapted to power the UV light source for a predetermined period of time. A reflector unit is disposed on one of the walls, the reflector unit including a reflective section projecting outwardly at an angle with respect to the wall. With the article placed in the chamber and the door closed and the electronic circuit activated, the UV lamp is illuminated for the predetermined period of time for sanitizing the article.

Related Applications

This application is a continuation application of U.S. patentapplication Ser. No. 15/082,027, filed Mar. 28, 2016, which is acontinuation application of U.S. patent application Ser. No. 13/431,632,filed Mar. 27, 2012, now U.S. Pat. No. 9,295,741, the contents of bothof which are incorporated herein by reference.

This application is related to U.S. patent application Ser. No.12/512,766, filed on Jul. 30, 2009, now U.S. Pat. No. 8,143,596, whichclaims the benefit of U.S. Provisional Patent Application No.61/268,365, filed on Jun. 11, 2009, all of which applications and patentare incorporated herein by reference in their entirety.

BACKGROUND

An apparatus and method for sanitizing articles is described and, moreparticularly, an apparatus and method using ultraviolet light forsanitizing articles between uses, such as medical instruments, tools andobjects, patient-care items, and the like.

Ultraviolet (UV) light of a particular range of wavelengths,intensities, and durations can kill or inhibit growth of microorganisms.Specifically, ultraviolet radiation in the range of 200 nanometer (nm)to 300 nm is effective against airborne and surface bacteria, viruses,yeasts, and molds. For most microorganisms, the peak inactivationwavelength is at or about 260 nm. Mercury lamps produce UV light veryefficiently at 254 nm and, therefore, this wavelength has become thestandard UV germicidal light wavelength.

UV light is used in healthcare facilities to disinfect surgical theatersand operating rooms. UV light is also used extensively in air and waterpurification applications in the food and beverage industry and insewage treatment. UV light can also be used to disinfect patient-contactitems like stethoscopes, thermometers, blood pressure cuffs, andoximeters, as well as doctor and staff-carried items such as cellphones, eMARs scanners, penlights, scissors, PDAs/tablets/laptops, andother easily contaminated, and difficult-to-disinfect items. UV lightcan also disinfect hand-held and portable electronic devices and otherpersonal articles, including mobile (cellular) telephones, portablemusic and video players (e.g., MP3 and MP4 players), cameras, portableglobal positioning devices, and the like.

In conventional UV sanitization devices, the UV radiation sources arestationary or portable and can range in size from very large devices tosmall hand-held wands. However, a problem associated with UVsanitization is most articles or implements requiring sanitization willhave interior spaces and non-planar surfaces. Some will have multipleinvaginations which can harbor microbes, such as reusable grocery bags,sporting equipment including helmets and shoes, and the like. Typically,UV sanitization devices are inadequate to irradiate the non-planarsurfaces of articles at varying distances from the UV radiation sources.As a result, some surfaces of the articles are not reached by UVirradiation.

For the foregoing reasons, there is a need for a new device forsanitizing articles, particularly articles having an interior space andnon-planar surfaces that are difficult to reach with conventional UVirradiation.

Summary

An apparatus is provided for sanitizing an article, the apparatuscomprising a housing including a plurality of walls defining an enclosedinternal chamber and having an opening at a door side into the chamber.A door is configured to selectively close the door side of the housingfor substantially sealing the chamber. A UV light source is disposedinternally of the housing for irradiating the chamber, and an electroniccircuit is electrically connected to the UV light source and adapted topower the UV light source for a predetermined period of time. Areflector unit is disposed on at least one of the walls, the reflectorunit including a reflective section projecting outwardly at an anglewith respect to the at least one of the walls. With the article placedin the chamber and the door closed and the electronic circuit activated,the UV lamp is illuminated for the predetermined period of time forsanitizing the article.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present invention, referenceshould now be had to the embodiments shown in the accompanying drawingsand described below. In the drawings:

FIG. 1 is a front perspective view of an embodiment of a device forsanitizing articles with a door in a closed position.

FIG. 2 is a front elevation view of the sanitizing device shown in FIG.1 with the door in an open position.

FIG. 3A is a longitudinal cross-section view of the sanitizing deviceshown in FIG. 1 taken along line 3A-3A of FIG. 2.

FIG. 3B is a longitudinal cross-section view of the sanitizing deviceshown in FIG. 3A with the mesh cages removed.

FIG. 4 is a close-up cut-away perspective view of an embodiment ofreflector units on a bottom surface of the sanitizing device shown inFIG. 2.

FIG. 5 is a cross-section view of the sanitizing device shown in FIG. 1taken along line 5-5 of FIG. 2.

FIG. 6 is a side elevation view of an embodiment of a reflector unit foruse in the sanitizing device shown in FIG. 1.

FIG. 7 is a cross-section view of the sanitizing device shown in FIG. 1taken along line 7-7 of FIG. 2.

FIG. 8 is a perspective of an embodiment of a tray for use in thesanitizing device shown in FIG. 1.

FIG. 9 is a rear elevation view of the sanitizing device shown in FIG. 1with a partial cover panel removed.

FIG. 10 is a top plan view of the sanitizing device shown in FIG. 1.

DESCRIPTION

Certain terminology is used herein for convenience only and is not to betaken as a limitation on the invention. For example, words such as“upper,” “lower,” “left,” “right,” “horizontal,” “vertical,” “upward,”and “downward” merely describe the configuration shown in the FIGs.Indeed, the components may be oriented in any direction and theterminology, therefore, should be understood as encompassing suchvariations unless specified otherwise.

As used herein, the term “article” is deemed to mean any portable,potentially contaminated object or item of porous or non-porous materialsuspected to be a fomite or vector of pathogens and diseasetransmission.

As used herein, the terms “bulb” or “lamp” is deemed to mean any sourceof UV light.

As used herein the terms “disinfect” and “sanitize” is deemed to meanthe expectation that bacterial count will be substantially reduced onobjects and items irradiated with UV light.

As used herein, the term “reflector unit” means a collection ofreflective structures that together reflect at least 60% of light havinga frequency between 100 nm to 290 nm.

A device for sanitizing an article is shown in FIG. 1 and generallydesignated at 20. The sanitizing device 20 comprises a housing 22constructed of a material that is impervious to UV radiation. In oneembodiment, the housing 22 is formed from polished, reflective aluminumsheeting. The housing 22 is substantially cube-like in shape, includinga partial front wall 24 defining an opening 26, side walls 28, and aninner rear wall 30 and an outer rear wall 31 (not visible in FIG. 1).The walls 24, 28, 30, 31 of the housing 22 are joined adjacent theiredges by a ceiling 32, a roof 35 spaced from the ceiling and a floor 34.The opening 26 in the front wall 24 is sealed by a sliding tambour door36, which provides access to inside the housing 22. Optionally, thehousing 22 can include a UV-resistant viewing window 39 that allows auser to view the inside of the sanitizing device 20 during operationwhile avoiding exposure to UV radiation. The housing 22 is sized andshaped to receive an article to be sanitized. The dimensions of thehousing 22 may be determined by the field of use. In the embodimentshown in the FIGs., the sanitizing device 20 may be placed on a cart 37for mobility of the device. Alternatively, the sanitizing device 20 canbe mounted to a wall or placed on a table or on the ground. It isunderstood that the size of the housing 22 or the opening 26 can varydepending on the article to be disinfected. All commercially viablesizes are contemplated.

Referring to FIG. 2, the housing 22 defines an open interior chamber 38formed by the inner surfaces of the front and side walls 24, 28, theinner surface of the inner rear wall 30, and inner surfaces of theceiling 32 and the floor 34. The opening 26 in the front wall 24 allowsthe user to access the chamber 38 for inserting and removing articles tobe sanitized. The chamber 38 is configured to accommodate at least onesource of UV radiation with a wavelength and intensity suitable forsanitization of the article. The sanitizing device 20 may furthercomprise one or more means for supporting articles to be sanitized. Inaddition, one or more reflector units 40 project upwardly from the floor34 for reflecting UV light from the UV lamps 42 upwardly toward thearticles disposed within the chamber 38. As described in more detailbelow, the reflector units 40 provide a more thorough and uniformdistribution of UV light to all surfaces within the chamber 38, and inparticular, the underside of the article supporting means and thearticles.

The door 36 is made of, or includes a layer, lining, or coating of, amaterial that is substantially opaque to UV radiation. The door 36 isslidingly received in a track 44 formed in the front wall 24 of thehousing 22 (FIGS. 3A and 3B). The door 36 is slideable in the track 44for moving between an open position (FIG. 2) wherein articles can beinserted into, or removed from, the chamber 38, and a closed position(FIG. 1) wherein the chamber 38 is closed so as to substantially preventthe escape of ultraviolet radiation from the chamber 38. A handle 46 ofantimicrobial copper alloy may be provided on the door 36 for moving thedoor 36 between the open position and the closed position. A suitablelight seal can be provided at a junction where the front wall 24 of thehousing 22 and the leading edge of the door 36 engage when the door 36is in the closed position. The seal may include any suitable materialwhich inhibits the passage of light, such as a rubber or a felt gasket,or the door 36 may have a close or overlying fit between the door 36 andthe front wall 24 of the housing 22.

Although the door 36 is shown as a tambour door, it is contemplated thatthe door 36 could alternatively be a hinged door or any othercommercially suitable configuration. For example, the hinged door may beattached to the housing 22 by hinges disposed between the adjacent edgesof the housing 22 and the door that allows the door to be selectivelyopened and closed.

The inner surfaces of the walls 24, 28, 30, the floor 34 and the ceiling32 of the housing 22 are provided with a reflective material. A suitablematerial is aluminum, and more particularly, polished aluminum. Othermetals may be used, such as polished zinc or stainless steel.Alternatively, a reflective coating may be placed on the inner surfacesof the walls 24, 28, 30, floor 34 and ceiling 32, such as magnesiumcarbonate. The reflective surfaces reflect the emitted UV radiation inorder to ensure that all surfaces of the article to be irradiatedreceive comparable amounts of UV irradiation. In practice, areflectivity in excess of 65% is desirable. In one embodiment, apolished aluminum can achieve up to 97% reflectivity, a polished zincsurface can achieve about 80% reflectivity, while the correct selectionof magnesium carbonate/oxide coating can achieve about 70% reflectivity.The reflective inner surfaces of the walls 24, 28, 30, the floor 34 andthe ceiling 32 of the housing 22 can be smooth, or if desired, may be asculptured or otherwise non-planar configuration to enhance or directthe reflected radiation. In one embodiment, the inside surface of thedoor 36 may also be provided with a reflective material.

As shown in FIGS. 4 and 5, the floor 34 of the housing 22 includes aplurality of spaced reflector units 40. Referring to FIG. 6, each of apair of sides of a reflector unit 40 includes at least three sections, aprimary wall section 48, a first end wall section 50, and a second endwall section 52. The first and second end wall sections 50, 52 extendangularly inwardly from the primary wall section 48. Each of the threewall sections 48, 50, 52 extending upwardly from the floor 34 and aredisposed off normal with respect to the floor 34. The angle (H) betweenthe floor 34 of the housing 22 and each of the wall sections 48, 50, 52is at least about 135 degrees. The wall sections 48, 50, 52 are joinedat an apex of the reflector unit 40 forming an elongated pyramidalprojection such that, when viewed from the front, the reflector unit 40appears to have a triangular shape. In alternative embodiments, thereflector unit 40 could include four or more wall sections and be formedof shapes such that, when viewed from the front, the reflector unit 40appears to have a square, rectangular, pentagonal, hexagonal, or anyother commercially viable shape. Of course, depending on the shape ofthe reflector unit 40, the shape and number of reflective wall sectionswill likely vary.

The reflector units 40 can be composed of the same reflective materialas the inner surfaces of the walls 24, 28, 30 of the housing 22.Alternatively, the reflector units 40 can be one or more commerciallysuitable materials, including, for example, mirrors, powder-coated andother metal sheets. The reflective wall sections 48, 50, 52 could alsobe dimpled or bumpy.

The reflector units 40 are positioned on the floor 34 with respect tothe UV lamps 42 so that at least some UV radiation that would otherwisebe emitted by the UV light sources in a direction other than at thearticles is reflected upwardly toward the articles. Specifically, thelongitudinal axis of the reflector units 40 adjacent the front and rearof the chamber 38 is aligned with the mid-line C (FIG. 5) between theside walls 28 of the chamber. The intermediate V-shaped reflector unit40 is positioned such that a line extending between each of the pairs ofopposite corners of the housing 22 would be perpendicular to the primarywall sections 48 of the intermediate reflector unit 40.

With this arrangement of the reflector units 40, the UV radiationintensity on the various surfaces of the article is more consistent,which increases the efficiency of use of the UV radiation and maximizesthe exposure of all surfaces of the articles to the UV radiation. Theresult is a sanitizing device 20 requiring fewer UV lamps 42 and ashorter duration of exposure to the UV light to disinfect the article.It is understood that the reflector units 40 can be disposed at anyposition on the inner surface of the walls 24, 28, 30, the ceiling 32 orthe floor 34 of the housing 22 to achieve this result. All commerciallysuitable configurations for the reflector units 40 are contemplated, andsuch configurations will likely depend on the size and dimensions of thehousing 22 and the articles to be irradiated.

Any commercially suitable source of UV radiation is contemplated for usewith the sanitation device 20. The UV radiation source may include coldcathode UV tubes, LED's, and low, medium, or high vapor mercury lamps.The UV radiation source has a suitable wavelength that falls within thewavelength range of about 220 nm to about 300 nm, preferably at leastsubstantially in the range of 235 nm to about 280 nm, and morepreferably about 250 nm to about 275 nm. In this range, the UV radiationis highly effective against microorganisms.

In the embodiment shown in FIGS. 2, 3B and 7, the source of UV radiationincludes a plurality of elongated fluorescent UV lamps 42 disposed on aninner surface of the housing 22 and positioned to substantiallyirradiate the interior chamber 38 and any article in the chamber. A UVlamp that emits light within the preferred wavelength range and issuitable for use in the sanitizing device 20 is a Model No. GTL 18 orGTL 24 high output, 72 watt UV germicidal lamp, available from AmericanUltraviolet Company of Lebanon, Ind. These UV lamps are 15 mm glasstubes with a single end power connector and a protective boot and areTeflon-coated for containment in case of breakage. In addition, these UVlamps produce UV light at an intensity of 7200 μW/cm² at a distance ofabout twelve inches. The UV lamps are approximately 18 inches and 24inches in length, respectively, including three inches attributed to theend connectors. Although the UV lamps are shown having elongated tubularbulbs, it is contemplated that other commercially suitable sources of UVlight could be used of any convenient size or shape of UV lamp or bulbmay be employed. Even a plurality, or a bank, of UV LED's may beemployed, as long as they emit the proper wavelength of UV light.

The plurality of UV lamps 42 are attached to pairs of tube holders 78and depend from the inside surface of each of the side walls 28, theinner rear wall 30 and the ceiling 32 of the housing 22. The UV lamps 42are oriented radially inward towards the center of the chamber 38 so asto provide UV radiation from all directions to maximize the exposure ofthe articles within the chamber 38. The UV lamps are spaced about 1½inches from the inner surfaces of the housing 22. Two UV lamps 42 areprovided on each side wall 28 extending generally vertically and areevenly spaced between the floor 34 and the ceiling 32. The front UV lamp42 on each side wall 28 is spaced about 4 inches from the front wall 24,and the rear UV lamp 42 on each side wall 28 is spaced about 8 inchesfrom the rear wall 30. The front and rear UV lamps 42 are spaced fromeach other about 10 inches on center. The single UV lamp 42 on the rearwall 30 is disposed along the central longitudinal axis of the rear wall30 and is evenly spaced between the ceiling 30 and the floor 34. The UVlamp 42 on the ceiling 32 is disposed along the central longitudinalaxis of the ceiling 32 and is evenly spaced between the front wall 24and the rear wall 30. The distance from each of the UV lamps to acentral plane passing through the middle of the chamber 38 is abouteleven inches. In one embodiment of the sanitizing device 20 based onthese relative dimensions, the reflector units 40 may each be about 4inches in length and project upwardly about ¾ inches from the floor 34of the housing 22. The front end of the front reflector unit 40 is about½ inches from the front wall of the housing 22 and the rear end of therear reflector unit 40 is about three inches from the rear wall 30. Forthe V-shaped reflector unit 40, the length of four inches is measuredfrom the point of the “V” to each end.

It is understood that the UV lamps 42 could be disposed at non-rightangles. It is further understood that the specific number, size, andorientations of each of the UV lamps 42 will likely vary depending onthe size and type of UV lamps used, the article to be disinfected, andthe sizes and dimensions of the housing 22. The UV lamps 42 can bedisposed in any suitable locations and oriented such that articleswithin the chamber 38 are exposed to adequate amounts of UV radiationfor sanitization. A wire mesh protective cage 80 surrounds each of theUV lamps 42.

The article supporting means may comprise an article support suitablefor use in the environment of the chamber 38, such as a drawer, tray,shelf system, or receptacles for receiving and supporting articleswithin the housing 22. In the embodiment shown in the FIGs., the articlesupporting means is a plurality of trays 54 positioned at differentlevels in the chamber 38. Referring to FIG. 8, each tray 54 comprises aplatform disposed in a flat configuration. The tray 54 is formed from alight-transmissible material made of wire mesh or lattice such as, forexample, 50 mm wire mesh. The tray 54 is configured to have some depththereby defining a recess for accommodating the article. Opposedchannels 56 are provided on the inner surfaces of the side walls 28.Elongated downwardly curved flanges 57 are positioned on opposite sidesof the trays 54 for slidably receiving the channels 56. A hook 58 isprovided on the back edge of the tray 54. The hook 58 captures the wiremesh of the cage 80 surrounding the UV lamp 42 on the rear wall 30 tosecure the trays 54 in an inserted position. The trays 54 can be removedfor cleaning or for loading articles on the trays 54.

The relative positioning of the UV lamps 42, the reflector units 40, andthe trays 54 is such as to ensure that all surfaces of the article andthe upper and lower surfaces of the trays 54 are exposed to sufficientamounts of UV irradiation through the apertures of the wire mesh. Theeffect of “shadows” caused by the bars of the mesh coming between thelower surface of the article when supported on the mesh and the UVradiation are minimized. The channels 56 and flanges 57 are made ofreflective material to further maximize the distribution of UVradiation. A minimal contact area between the article and the mesh ofthe tray 54 may be acceptable.

Referring now to FIG. 9, the outer surface of the rear wall 30 of thesanitizing device 20 accommodates a control box 60. The control box 60preferably has a removable cover panel (not shown) for allowing accessto a circuit board supporting the wiring and circuitry for repair,removal, and replacement. The circuit board carries a controller 62 forcontrolling operation of the sanitizing device 20 and a power supply 64for providing power to the controller 62, such as electric cord and plug(not shown). The power supply cord 64 is connected to a transformer 66to provide electrical power to the circuit. The controller 62 cancontrol the delivery of power to the UV lamps 42 to be turned on or off,as well regulating other electrical components of the sanitizing device20 including, for example, one or more sensors.

A first sensor 68 senses or detects whether the door 36 is in the openposition or the closed position and signals the controller to controloperation of the sanitizing device 20 accordingly. Alternatively, asensor may be activated upon closing the door. The sensor can include,but is not limited to, one or more of a depression switch, electricalcontacts, an optical sensor or other sensor known in the art fordetermining the relative positions of the door and the front wall 24 ofthe housing 22. In one embodiment, the sensor comprises a contact on thehousing 22 and a magnet 69 in the door 36, the completed circuitactivating the UV radiation source only when the door 36 is in theclosed position to enclose the chamber 38. For example, the ultravioletradiation source is disabled from emitting ultraviolet light when thedoor 36 is in the open position and is enabled to emit ultraviolet lightwhen the door 36 is in the closed position.

Each UV light source is electrically connected to an electronic ballast,which provides resistance to stabilize current in the circuit createdwhen the sanitizing device 20 is attached to a power source via thepower supply cord 64. In a preferred embodiment, ballast is operationalwith 100/200 VAC at 50/60 HZ.

In one embodiment, the controller 62 activates the ultraviolet radiationsource for a first predetermined period of time when the sensor 68senses that the door 36 is in the closed position. The predeterminedperiod of time may vary depending on the strength of the UV lightsource. In one embodiment of the sanitizing device 20 using the 72 wattUV lamps identified above, it is estimated that between about 30 andabout 60 seconds would be sufficient to eliminate most bacteria presenton an article. A timer is used to control the length of time the UVsource is powered. The controller 62 automatically turns off the UVlight source at the set time on the timer after, for example, the about30 to about 60 seconds, and may include an audible signal (beep, chime,etc.) to let the user know the cycle is finished. The controller may inaddition to, or alternately, activate the UV radiation source based on asignal from a manual interface, such as a switch 70 (FIG. 1) or otherinterface located outside of the sanitizing device 20 that a user canselect to manually activate the controller 62. A plurality of switchesmay also be provided, and additional functionality may be included,including different settings for different articles to be sanitized,different durations of the sanitization cycle, different power levelintensities for the UV lamps, and the like.

One or more indicator lamps or displays may be provided on the outsideof the housing 22 to indicate the status of the sanitizing device 20.For example, a lamp indicator light may show whether power is being sentto the sanitizing device 20. A light 82 may also be provided in thechamber 38 (FIG. 7), which light 82 is activated for the user when thedoor 36 is in the open position. All other commercially viable safetysystems are contemplated. For example, a vent 84 is provided between therear walls 30, 31 of the housing 22 and exits via the roof 35. Thesanitizing device 20 could also require a key or security code beentered prior to activation.

In operation, the user moves the door 36 to the open position by rollingupwardly to expose the chamber 38 and the trays 54. The trays 54 areaccessed by manually detaching the hooks 58 and pulling the trays 54outwardly. The trays 54 slide along the channels 56 and may becompletely removed. Articles to be irradiated are then placed on one ormore of the trays 54. The trays 54 are then returned to the chamber 38and pushed inwardly to the closed position by pressing on the front ofthe trays 54 and attaching the hooks 58 to the wire mesh of the cage 80.The user moves the door 36 to the closed position to enclose thearticles within the chamber 38. The sensor 68 is activated upon closingof the door 36 for signaling the controller 62 that the door is in theclosed position. The sanitizing device 20 is activated by pressing theoutside switch 70. Upon activation, the controller 62 directs power toenergize the UV lamps 42 to sanitize the articles.

When the sanitization device 20 is activated, UV light is directedthroughout the chamber 38 and onto the articles to be disinfected. UVlight is reflected off of the reflective inner surfaces of the walls andthe surfaces of the reflector units 40 ensuring exposure of all surfacesof the articles to UV light. The effect is UV light is directed from theUV lamps 42 in all directions, including irradiating the underside ofthe articles through the apertures in the trays 54. The UV light killssignificant amounts of microorganisms that may be on the articles,thereby sanitizing, or disinfecting, the articles. The articles aresubjected to a dose of UV light corresponding to the UV light intensityas a function of time and distance of the UV lamps from the articles.Dose response levels are unique to each microorganism. Additionally,different wavelengths of UV light have different inactivation ratesdepending on the microorganism. It is understood that such processparameters are predetermined to affect the amount of radiation such thatan article receives UV light sufficient to destroy microorganisms on thesurfaces of the articles and to ensure a consistently effectivereduction in microbial numbers.

After a predetermined time sufficient to achieve a desired level ofsanitization, the controller 62 deactivates the UV radiation sources.When the sanitization cycle is completed, the display may indicate assuch. If the sensor 68 detects an attempt to open the door 36 while theUV radiation sources are activated, the controller immediately shuts offpower to the UV radiation sources.

It is contemplated that the sanitizing device 20 described and shownherein could be configured to sanitize all manner of articles andequipment including, for example, cosmetics or cosmetic implements suchas eyeliner brushes and mascara brushes, and even small cosmetic itemsthemselves such as personal items including compacts, and the like;kitchen utensils and tools such as cutting boards, and larger sizeditems including wheel chairs, strollers, and other sizes of shoppingcarts shopping baskets. Depending on the size and dimension ofsanitizing device 20, and the type of equipment to be disinfected, thenumber of reflective units, and their configurations, can be varied.Regardless of the article to be sanitized, the sanitizing device 20design allows for considerable adjustment of the amount of energystriking the article by selecting the number of lamps used, the distanceof those lamps from the article, and the length of time that the articleis exposed to UV light. The sanitizing device 20 can conveniently andeffectively disinfect articles in a short period of time.

The sanitizing device 20 described and shown herein was tested todetermine the efficiency of the sanitizing device 20 versus aconcentration of Clostridium difficile (C. difficile), Staphylococcusaureus (S. aureus), and Acinetobacter baumannii (A. baumannii) using a60 second exposure time and a 120 second exposure time. Microorganismpreparation included inoculating tryptic soy agar (TSA) petri plateswith S. aureus and A. baumannii and incubating the plates for 22-26hours at 30-35° C. Similarly, reinforced clostridial medium plus agar(RCM+ Agar) petri plates were inoculated with C. difficile and incubatedfor 46-52 hours at 30-35° C. in an anaerobic chamber containing anAnaeroGen Pak™.

Serial dilutions of each culture were prepared in 7.2 pH buffer. Next,0.1 mL of 10³ CFU/mL concentration of each organism were plated induplicate and incubated as described above. The concentration of eachorganism was calculated by multiplying the count acquired by 10 due tothe 10⁴ CFU/mL dilution being used for spiking.

Pre-poured plates were then spiked. Specifically, 18 TSA plates wereinoculated with 0.1 mL of 10⁴ CFU/mL of S. aureus and spread with asterile hockey stick and another 18 TSA plates were inoculated with 0.1mL of 10⁴ CFU/mL of A. baumannii and spread with a sterile hockey stick.Similarly, 18 RCM+ Agar plates were inoculated with 0.1 mL of 10⁴ CFU/mLof C. difficile and spread with a sterile hockey stick.

The organism-spiked plates were then placed in the sanitizing device 20on each of the top, middle and bottom trays. On the top tray, plateswere placed at the right front, back middle and left back of the tray.On the middle tray, plates were placed at the right back, middle andleft middle of the tray. On the bottom tray, plates were placed at theright middle, middle, and left front of the tray. Lids were removed fromthe plates and the plates set agar side up. The sanitizing device 20 wasactivated for 60 seconds. The sanitizing device was deactivated and thelids replaced on the plates and the plates removed. These steps wererepeated for each organism.

In a second run, the organism-spiked plates were in the sanitizingdevice 20 on each of the top, middle and bottom trays. On the top tray,plates were placed at the middle front, left back and right back of thetray. On the middle tray, plates were placed at the middle back, middleand left front of the tray. On the bottom tray, plates were placed atthe right front, middle front, and left back of the tray. Lids wereremoved from the plates and the plates set agar side up. The sanitizingdevice 20 was activated for 120 seconds. The sanitizing device wasdeactivated and lids replaced on the plates and the plates removed.These steps were repeated for each organism.

The UV treated plates of S. aureus and A. baumannii were incubated at30-25° C. for 44-52 hours. The UV treated plates of C. difficile wereincubated at 30-35° C. for 44-52 hours in an anaerobic jar containing anAnaeroGen Pak™. The organism spike count from untreated plates served asa positive control to confirm that TSA and RCM+ Agar media supported thecorrect bacterial growth. An un-spiked TSA plate and an un-spiked RCM+Agar plate were also incubated to confirm that the plates were notcontaminated.

The percent kill of each organism for each exposure time was calculatedby dividing the count after the exposure to UV light by the originalconcentration of the organism and then multiplying by 100. Log₁₀reduction of each organism for each exposure time was calculated byconverting each organism count to a log₁₀ number. For example, 213CFU/mL equals 2.33 Log₁₀. The Log₁₀ decrease of each organism for eachexposure time was found by calculating the difference between the Log₁₀of the original concentration of the organism and the Log₁₀ after the 60and 120 second exposure to UV.

The sanitizing device 20 for all plates at all locations and for bothexposure times achieved a 100% killing of S. aureus and A. baumannii.The sanitizing device 20 for all plates at all locations and for bothexposure times achieved a 100% killing of C. difficile, except for themiddle tray at the middle and left middle locations, which achieved99.9% reduction in the organism. Converting the organism counts to aLog₁₀ number, the reduction in S. aureus at all locations was 5.80 log₁₀and the reduction in A. baumannii at all locations was 6.15 log₁₀ .Although one colony of was found on two of the C. difficile plates fromthe 120 second exposure study, the log₁₀ of 1 is 0 so the log₁₀reduction for all locations was 4.00.

Although the apparatus and method for sanitizing articles has been shownand described in considerable detail with respect to only a fewexemplary embodiments thereof, it should be understood by those skilledin the art that we do not intend to limit the invention to theembodiments since various modifications, omissions and additions may bemade to the disclosed embodiments without materially departing from thenovel teachings and advantages of the invention, particularly in lightof the foregoing teachings. Accordingly, we intend to cover all suchmodifications, omission, additions and equivalents as may be includedwithin the spirit and scope of the invention as defined by the followingclaims. In the claims, means-plus-function clauses are intended to coverthe structures described herein as performing the recited function andnot only structural equivalents but also equivalent structures. Thus,although a nail and a screw may not be structural equivalents in that anail employs a cylindrical surface to secure wooden parts together,whereas a screw employs a helical surface, in the environment offastening wooden parts, a nail and a screw may be equivalent structures.

We claim:
 1. An apparatus for sanitizing an article, the apparatuscomprising: a housing including a plurality of walls defining anenclosed internal chamber and having an opening at a door side into thechamber; a door configured to selectively close the door side of thehousing for substantially sealing the chamber; a UV light sourcedisposed internally of the housing for irradiating the chamber; anelectronic circuit electrically connected to the UV light source andadapted to power the UV light source for a predetermined period of time;and a reflector unit disposed on at least one of the walls, thereflector unit including a reflective section projecting outwardly at anangle with respect to the at least one of the walls, wherein with thearticle placed in the chamber and the door closed and the electroniccircuit activated the UV lamp is illuminated for the predeterminedperiod of time for sanitizing the article.
 2. The apparatus forsanitizing an article as recited in claim 1, further comprising a trayconfigured to be received in the chamber of the housing, the adapted forsupporting the article.
 3. The apparatus for sanitizing an article asrecited in claim 2, wherein the tray comprises a wire mesh.
 4. Theapparatus for sanitizing an article as recited in claim 1, wherein theUV light source provides an intensity of about 7200 μW/cm² of UV lightat about one foot.
 5. The apparatus for sanitizing an article as recitedin claim 1, the reflective section of the reflector unit is angled withrespect to the wall by at least about 135 degrees.
 6. The apparatus forsanitizing an article as recited in claim 1, wherein the plurality ofthe walls of the housing comprises a front wall and an opposite rearwall, a pair of side walls interconnecting the front wall and the rearwall, a floor interconnecting the lower edges of the front wall, therear wall and the side walls, and a ceiling interconnecting the upperedges of the front wall, the rear wall and the side walls.
 7. Theapparatus for sanitizing an article as recited in claim 6, wherein theUV light source extends along the rear wall.
 8. The apparatus forsanitizing an article as recited in claim 6, further comprising aplurality of UV light sources extending along the plurality of the wallsof the housing.